Understanding Diachronic Works in RDA Operations Committee

1. Diachronic works in RDA PCC Operations Committee meeting Library of Congress, 2 May 2019

2. What is a diachronic work? • A diachronic work is a work that is planned to be embodied over time, rather than as a single “act of publication”. • The essence of a diachronic work is a plan for the change of content. • Change of content = extension of content

3. How is content extended? • By accumulation (the addition of content in discrete physical or logical units): successive works • By replacement (new content is integrated with—and may replace—existing content): integrating works • In RDA these methods are specified by the extension plan element of the work entity

4. What is the extension plan element? • The extension plan element is a categorization combining values from two extension attributes of the RDA/ONIX Framework for Resource Categorization: • Extension mode (succession or integration) • Extension termination (whether or not period of extension has a predetermined end: determinate or indeterminate) • There is an additional category for resources with a static (non-diachronic) plan

5. How are the values of the extension plan element recorded? • There is an RDA vocabulary encoding scheme (VES) for extension plan, with five possible values: • Integrating determinate plan • Integrating indeterminate plan • Static plan • Successive determinate plan • Successive indeterminate plan

6. Integrating determinate plan • ROF extension mode • INTEGRATION • ROF extension termination • DETERMINATE • RDA extension plan • INTEGRATING DETERMINATE

7. Integrating indeterminate plan • ROF extension mode • INTEGRATION • ROF extension termination • INDETERMINATE • RDA extension plan • INTEGRATING INDETERMINATE

8. Static plan • ROF extension mode • N/A • ROF extension termination • N/A • RDA extension plan • STATIC

9. Successive determinate plan • ROF extension mode • SUCCESSION • ROF extension termination • DETERMINATE • RDA extension plan • SUCCESSIVE DETERMINATE

10. Successive indeterminate plan • ROF extension mode • SUCCESSION • ROF extension termination • INDETERMINATE • RDA extension plan • SUCCESSIVE INDETERMINATE •  Serial work

11. How does this relate to IFLA LRM? • IFLA LRM (5.8 Modelling of serials) regards any serial as “a distinct instance of the work entity” [i.e. serials have a WEM lock] and uses specific relationships among these instances to connect them • The modeling of diachronic works in RDA is extrapolated from this modeling of serials in IFLA LRM

12. So does a work with a diachronic extension plan have a WEM lock? • Yes, any work with a diachronic extension plan may berealized in one and only one expression and embodied in one and only one manifestation, a 1:1 cardinality in each case • Any work with a static extension plan adheres to the standard WEMI cardinality: it may be realized in one or more expressions and embodied in one or more manifestations, a 1:M cardinality in each case

13. Come again? • RDA explains this in terms of transformation boundaries • A transformation boundary is a stage at which a work is treated as a new work separate from the existing work • For static works, a difference in content between two expressions is a necessary but insufficient indicator that each expression realizes a different work (no transformation boundary has necessarily been crossed) • For diachronic works, the potential for a difference in content (inherent in the fact that content is embodied over time) between two manifestations is sufficient in itself to indicate that each manifestation embodies a different expression and those expressions realize different works (the transformation boundary has been crossed)

14. Work is a transformation of Work [LRM-R22] • Transformation by audience • Carrier version • Language version • Regional version • Transformation by genre • Transformation by policy • Transformation by extension plan • Transformation by style

15. So how does this affect continuing resources? • Not much • For CR, RDA is simply implementing the IFLA LRM modeling of serials • Aligns more closely with ISSN practice • Pretty much reflects current CONSER practice • Preferred title of translations and languages editions = title proper

16. What about multipart monographs issued over time? • RDA treats any multipart monograph issued over time as a diachronic work with a successive determinate extension plan • RDA no longer treats “multipart monograph” as a mode of issuance • Extension plan: successive determinate plan • Mode of issuance: multiple unit

17. Can you give an example? • Encyclopædia Britannica (3rd edition) • Initially published from 1788 to 1797 in ca. 300 fascicles • Volume title pages issued later, all with “1797” as date of publication

18. Now it’s getting personal… • w1 (static work): My dissertation • e1 Typescript (with diskettes in pocket) • e2 Typescript (without diskettes or pocket) • m1 Microfilm • m2+ Publish-on-demand from microfilm (several size and binding options) • m3 Digitized microfilm (ProQuest online products) • w2 (diachronic work): My dissertation, slightly abridged and published under what I thought was a catchier title in the vain hope of attracting a wider audience (or indeed any audience at all) • W2.1-2.2 Contributions to 2 successive issues of Cataloging & Classification Quarterly

19. How do I now bring together works that RDA might formerly have considered expressions of a single work? • RDA permits closely related works to be treated as work groups • Descriptions of these works might be brought together by recording an appellation of work group (assigned from a vocabulary encoding scheme) as part of the description of each work

20. For example, The Economist • Authorized access point for work group: Economist (London, England : 1843) • Drawn from LCNAF vocabulary encoding scheme (VES) • LCCN: no2019022928 http://id.loc.gov/authorities/names/no2019022928 • Identifier for work group: 0013-0613 • Drawn from ISSN-L vocabulary encoding scheme (VES) • IRI: https://www.wikidata.org/wiki/Q180089

21. For example, Encyclopædia Britannica • Authorized access point for work group: Encyclopaedia Britannica • Drawn from LCNAF vocabulary encoding scheme (VES) • LCCN: nr89013909 http://id.loc.gov/authorities/names/nr89013909 • IRI: https://www.wikidata.org/wiki/Q455

22. The future: relationships? • Historically, we used uniform titles to bring together expressions and manifestations of works in the context of an alphabetical catalog. This has created a sizeable store of legacy data predicated on this mechanism for collocation • Prospectively, appellations of work groups may serve this purpose (though the underlying semantics may be a bit messy) • In a linked data environment, however, relationship matrices may increasingly serve this purpose: • Work A transformation by extension plan of Work B

23. The present: pragmatic question (MARC / BIBFRAME) • How will one identify an RDA authorized access point for work group (identifying the members of a work group) in MARC or BIBFRAME? • Part of the larger question of mapping from RDA to MARC and/or BIBFRAME and vice versa • Currently we map in our heads, which is not really a satisfactory Linked Data solution

24. Fin ejones@nu.edu